During reconstruction, the black codes
a)
protected the constitutional rights and liberties of freed slaves.
b)
forced congress to do the bidding of former confederate politicians.
c)
were enacted by the radical republicans to prevent racial discrimination in the south.
d)
were laws passed by mainly southern states to keep african americans in a system of virtual slavery.

During Reconstruction, the Balck Codes d) were laws passed by mainly Southern states to keep African Americans in a system of virtual slavery. "In the United States, the Black Codes were laws passed by the Southern states in 1865 and 1866, after the Civil War. These laws had the intent and the effect of restricting African Americans' freedom, and of compelling them to work in a labor economy based on low wages or debt."